1. Field of the Invention
This invention pertains to construction equipment, and more particularly to apparatus that assists construction workers install building components.
2. Description of the Prior Art
Various equipment has been developed to lift heavy objects and to temporarily hold them in place. For example, automotive jacks of different designs and capacities are well known and in widespread use. For example, U.S. Pat. No. Des. 216,144 shows a typical prior jack that holds an object at a considerable height above a support surface. U.S. Pat. No. 3,995,565 discloses a jack-type cargo brace.
Telescoping supports are also well known. In many telescoping designs, relatively slidable columns are held in place by pins or similar elements. U.S. Pat. Nos. 5,201,488; 5,622,355; and 5,979,854 show examples of that kind of telescoping support. In other telescoping supports, relatively slidable columns are held in place by a clamping or friction device. U.S. Pat. Nos. 3,930,645; 4,083,530; 4,757,975; and 6,042,066 show representative telescoping support devices that use clamps or friction devices.
Another variation of columnar adjustable supports employs threaded members. Turning one of the members causes it to move linearly and adjust the distance between a support surface and a supported object. Typical thread-type supports may be seen in U.S. Pat. No. Des. 263,114; Des. 338,310; 3,737,134; 3,917,208; 3,920,220; 4,221,362; 4,581,863; 5,400,994; and 5,826,847.
The lifting and support devices described in the foregoing patents work well for their intended purposes. Nevertheless, they do have certain disadvantages. For example, the telescoping support column of the U.S. Pat. No. 3,737,134 requires a separate rod in order to use it. The jack post of the U.S. Pat. No. 4,221,362 requires a separate wrench to perform the length adjustments.
Thus, there is a need for further developments to adjustable supports.
In accordance with the present invention, an adjustable support is provided that greatly assists carpenters and other craftsmen to install bulky and heavy components in buildings. This is accomplished by apparatus that includes a carrier that is conveniently adjustable relative to a stand.
The stand includes a base and a lower post upstanding from the base. An upper post is slidable within the lower post along a stand longitudinal axis. The two posts are lockable to each other at desired locations relative to each other.
In the preferred embodiment, a threaded insert is fixed to the interior of the upper post at its top end. An adjuster has a threaded rod that mates with the insert threads. A disc on the adjuster is between the threaded rod and a short shaft that has a free end. The disc has an outer diameter considerably larger than the diameters of the threaded rod and the shaft.
According to one aspect of the invention, the carrier is a flat plate with a pipe fastened to the plate. The carrier pipe is sized to fit over the adjuster shaft, such that the carrier plate is generally perpendicular to the stand longitudinal axis and rests on the adjuster shaft free end. Turning the disc moves the adjuster and the carrier along the stand longitudinal axis.
In use, the base of the stand is placed on a support surface under the final installed location of the object such as a kitchen cabinet. The upper post is slid in the lower post to bring the carrier plate close to the final installed location of the cabinet. The stand is then locked. The cabinet is placed on the carrier plate. The adjuster disc is turned as required to raise or lower the cabinet to the desired final location. The relatively small area of the adjuster shaft free end produces only a small frictional torque on the carrier plate when the adjuster is turned. Consequently, there is little, if any, tendency for the cabinet to turn about the stand longitudinal axis with the adjuster shaft as the cabinet is brought into its final location. With the cabinet supported in place by the adjustable support, it can be permanently installed or otherwise worked on without concern for its moving from its desired location.
In the preferred embodiment, the upper post has a series of cross holes through it. The cross holes are spaced at predetermined intervals that correspond to the height of the lower post and to the height of the cabinet above the support surface. A pin is removeably inserted through a selected cross hole such that when the pin rests on the top of the lower post, the carrier plate is nominally at the distance of the bottom of the cabinet above the support surface. The cross holes and pin thus function to both quickly locate the carrier at approximately its correct position and also to provide a positive stop against the upper post sliding further into the lower post.
It is a feature of the invention that it temporarily stores selected tools associated with installing the cabinet. For that purpose, a tray is secured to the lower post. Small tools such as drill bits and screws can be stored in the tray. A hole in the tray is so dimensioned and located that when it receives a drill bit chucked in a conventional electric hand drill, the drill chuck rests on the tray. In that manner, the carpenter has the drill close at hand when he installs the cabinet.
Further in accordance with the present invention, the adjustable support is easily convertible to use for installing stairway handrails. In that case, a carrier having a pivotable cradle is used. The cradle has a trough to which are joined a pair of lugs. The trough has an apex that defines a plane that contains the stand longitudinal axis. The lugs straddle a cross tube on a pipe. A clamp provides a pivotal connection between the cradle lugs and the cross tube. The clamp enables the cradle to pivot about a centerline that is perpendicular to the stand longitudinal axis. The clamp also clamps the lugs against the cross tube at an angle relative to the stand longitudinal axis that matches the angle of the handrail relative to the stairway.
To meet regulatory codes, handrails must be located at a specific spacing from a wall. To assist supporting the handrails at the required spacing, the adjustable support base is constructed with a working edge that is at a specific distance from the stand longitudinal axis. Placing the base working edge against a toe plate of the stairway automatically locates the cradle trough at the proper spacing from the wall of the stairway.
In a modified embodiment of the invention, an adjustable support for installing handrails uses the same stand that is used for installing cabinets, but the carrier is offset from the stand longitudinal axis. The amount of the offset suits the distance between a working edge of the stand base and the stand longitudinal axis. The offset cradle is pivotable and clampable in generally the same manner as the non-offset cradle.
The method and apparatus of the invention, using a combination of adjustable components, thus greatly aids the installation of bulky objects in buildings. The probability of mis-positioning an object is remote, even though the object is too heavy for an unaided person to handle effectively.
Other advantages, benefits, and features of the present invention will become apparent to those skilled in the art upon reading the detailed description of the invention.